Body support with variable rotation restriction

ABSTRACT

A rail vehicle with a car body and a bogie including a bogie frame for holding wheels or wheel sets and a carrier connected to the bogie frame for supporting the car body is provided. A braking means is fastened between the carrier and the car body in order to provide running stabilization so as to dissipate a rotary movement between the car body and bogie by opposing the rotary movement with a counterforce. A preload means imparts an adjustable preload or pressure force to the braking means, wherein the preload is controlled during operation of the rail vehicle by a controller.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is the US National Stage of International Application No. PCT/EP2008/056003 filed May 16, 2008, and claims the benefit thereof. The International Application claims the benefits of Austrian Patent Application No. A1131/2007 AT filed Jul. 17, 2002. All of the applications are incorporated by reference herein in their entirety.

FIELD OF INVENTION

The invention relates to a rail vehicle with a car body and a bogie that comprises a bogie frame for accepting wheels or wheel sets and a carrier connected to the bogie frame for supporting a car body, and with a braking means attached between the carrier and the car body that is configured to set a dissipative counterforce against a rotational movement between car body and bogie frame.

BACKGROUND OF INVENTION

Braking means of this type are used to improve the driving stability of vehicles with bogies. Dampers, especially hydraulic dampers, that are attached between car body and bogie frame, are a conventional approach for suppressing rolling of the rail car body. Often—especially in the local mass transit area—it is not possible for reasons of space however to achieve the desired driving stability in this way. In this case friction plates that act between the car body and the bogie are arranged on a cross-piece of the bogie frame. These friction plates dissipatively restrict a rotary movement of the bogie in relation to the car body.

SUMMARY OF INVENTION

The disadvantage in such cases is that the proportional car body mass acting on the bogie is supported via the friction plates. The friction force generated thus depends directly on the weight of the car body. This frequently causes an undesired level of friction force, mostly the rotation resistance between bogie frame and car body is undesirably high when negotiating a curve. In addition disadvantages emerge as regards wear as well as less protection against derailment.

An object of the invention is thus to improve the application of the friction force and to overcome the said disadvantages.

This object is achieved by a rail vehicle of the type mentioned at the start in which the braking means inventively features an adjustable preload means for imparting an adjustable preload, with the preload preferably being able to be controlled during the driving operation of the rail vehicle.

Through this solution it is made possible in a simple and yet still efficient manner to adapt the rotation resistance of a bogie to the driving conditions in an optimum manner. If necessary there can also be provision for setting the preload during driving operation.

In a preferred embodiment of the invention the braking means features at least one friction surface lying horizontally on the carrier and the car body side respectively that is arranged outside the axis of the rotational movement between car body and bogie frame, with the friction surfaces of the carrier and of the car body able to be pressed onto each other with a pressure force able to be set by the preload means. In this case it is especially useful for the preload means to feature a hydraulic plunger that presses the friction surfaces against each other with an adjustable pressure force.

Preferably the carrier can be connected rigidly to the bogie frame or at least have a fixed connection in relation to rotations around a vertical axis.

To be able to adapt the rotation resistance to the characteristics of the driving operation a development is of advantage in which an assigned controller for the preload means controls the preload (or the pressure force respectively) during the driving operation of the rail vehicle. In this case it is of particular advantage for the controller to control the preload as a function of the speed of the rail vehicle. In addition the controller can set the preload value to zero if the speed falls below a predeterminable limit value.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention, along with further advantages, is explained in greater detail below on the basis of a non-restricting exemplary embodiment which is shown in the enclosed drawings. The drawings show:

FIG. 1 the bogie frame of a railway car in a longitudinal section;

FIG. 2 an associated overhead view; as well as

FIG. 3 an example of a characteristic of a speed-dependent control of the pressure force.

DETAILED DESCRIPTION OF INVENTION

The figures show the driving gear layout of a railway car in which the invention is realized. FIG. 1 is a sectional view along the vertical center plane of the railway car (shown in FIG. 2 as a dot and dash line m), while FIG. 2 depicts an overhead view with the car body removed.

The driving gear of the exemplary embodiment shown is realized as a bogie 1 with a bogie frame 2 and cross piece 3 arranged on said frame. The cross piece 3 carries a rolling collar 4 on which the car body 5 is supported rotatably around the axis A running vertically. In this manner the weight of the car body 5 is supported by the cross piece 3.

Two friction elements 6 are attached between the cross piece 3 and the car body 5, preferably outside the area of the rolling collar 4. These friction elements 6 are embodied for example as surfaces formed from plastic connected to the cross piece 3 and act against the underside of the car body 5 embodied as friction plates (e.g. from stainless steel). In a variant replaceable friction plates can also be attached to the car body underside.

To be able to better adjust the friction force achieved by the friction elements 6 to the driving conditions, such as driving speed and/or track, the friction elements 6 can be pressed by means of a hydraulic plunger 7 against the friction plates. The pressure force with which this occurs can be set via a hydraulic controller 8. The plunger 7 is mounted on the cross piece 3 and carries the two friction elements 6.

In an advantageous manner the hydraulic controller 8 can regulate the pressure force as a function of the driving behavior, especially the speed, of the rail vehicle. The controller is merely shown symbolically in FIG. 1; it is clear that the controller will be accommodated with the other rail car electronics in a compartment, e.g. in the rail car body.

An example of a control characteristic implemented by the controller 8 is shown in FIG. 3. For example the pressure force F, which is set for higher speeds to a maximum or end value F0, for lower speeds v, which especially occur when negotiating curves, can be set lower, or below a limiting speed vi, can even simply be set to zero. This allows a lower rotational resistance to be realized when negotiating curves which makes it easier to negotiate the curve. The maximum value F0 of the pressure force is set in respect of a friction force achieved, of which the value or order of magnitude respectively corresponds to conventional solutions with friction plates.

The pressure force can also be applied electromechanically instead of by means of a hydraulic plunger. In a simplified variant an adjustable mechanical spring element, preferably a disk spring package, can be used instead of the hydraulic plunger 7.

The hydraulic or electromechanical controller makes it easy to set a desired friction force via the pressure force without particular effort during operation and an individual adaptation to peculiarities of the driving operation (load, speed, etc.) is simple to implement. 

1-7. (canceled)
 8. A rail vehicle, comprising: a car body; and a bogie with a bogie frame for holding wheels or wheel sets and a carrier connected to the bogie frame for supporting the car body; and a braking means fastened between the carrier and the car body, the breaking means being configured to dissipate a rotary movement between the car body and bogie by opposing said rotary movement with a counterforce, wherein the braking means includes a preload means for imparting an adjustable preload.
 9. The rail vehicle as claimed in claim 8, wherein the braking means features at least one friction surface lying horizontally on the carrier and the car body side respectively that is arranged outside an axis of the rotational movement between car body and bogie frame, and wherein the friction surfaces of the carrier and of the car body are pressed onto each other with a pressure force set by the preload means.
 10. The rail vehicle as claimed in claim 9, wherein the preload means features a hydraulic plunger that presses the friction surfaces with adjustable pressure force against each other.
 11. The rail vehicle as claimed in claim 8, wherein the carrier is connected rigidly to the bogie frame or at least has a fixed connection in relation to rotations around a vertical axis.
 12. The rail vehicle as claimed in claim 9, wherein the carrier is connected rigidly to the bogie frame or at least has a fixed connection in relation to rotations around a vertical axis.
 13. The rail vehicle as claimed in claim 8, wherein a controller is assigned for the preload means for controlling the preload during the driving operation of the rail vehicle.
 14. The rail vehicle as claimed in claim 9, wherein a controller is assigned for the preload means for controlling the preload during the driving operation of the rail vehicle.
 15. The rail vehicle as claimed in claim 11, wherein a controller is assigned for the preload means for controlling the preload during the driving operation of the rail vehicle.
 16. The rail vehicle as claimed in claim 13, wherein the controller controls the preload as a function of the speed of the rail vehicle.
 17. The rail vehicle as claimed in claim 14, wherein the controller controls the preload as a function of the speed of the rail vehicle.
 18. The rail vehicle as claimed in claim 15, wherein the controller controls the preload as a function of the speed of the rail vehicle.
 19. The rail vehicle as claimed in claim 16, wherein the controller is configured to set the preload to zero when the speed drops below a predeterminable limit value.
 20. The rail vehicle as claimed in claim 17, wherein the controller is configured to set the preload to zero when the speed drops below a predeterminable limit value.
 21. The rail vehicle as claimed in claim 18, wherein the controller is configured to set the preload to zero when the speed drops below a predeterminable limit value. 